Process of manufacturing a hose fitting

ABSTRACT

Disclosed are a hose fitting comprising the following and a process for manufacturing the same: A hose fitting body composed of a head portion with a through hole made in the center of a pair of flat surfaces thereof, a base portion, and a sleeve all of which are formed out of a test tube-shaped substance by a plastic deformation, and a nipple integrally fixed on the inner circumferential surface of the sleeve. The hose fitting of this invention provides the following advantages of offering easy work for the bending the base portion, offering readiness for securing a necessary cross-sectional area as the fluid delivery hole of the base portion even when the base portion is bent greatly, light-weighted construction having a uniform wall thickness and requiring less raw material cost, and fixing nipple on the sleeve inner circumferential surface in a fluid-tight manner without brazing or drive fitting the nipple.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a hose fitting and a process for manufacturingthe same.

2. Description of the Prior Art

A hose fitting illustrated in FIG. 20 is known as a conventionalfitting.

The conventional hose fitting comprises a hose fitting body 1' and anipple 2'. The hose fitting body 1' is composed of a head portion 11'having a through hole 111' into which a bolt is to be inserted, a baseportion 12' continuing from the head portion 11', and a cylindricalsleeve 13' continuing from the base portion 12'. The nipple 2' is fixedintegrally on the bottom surface of the sleeve 13'. The sleeve 13' isformed coaxially with the nipple 2', and is caulked to fix a hose 9after inserting the hose 9 into the nipple 2'. Further, a fluid deliveryhole 211' of the nipple 2' is connected to a fluid delivery hole 121' ofthe base portion 12'.

In the conventional hose fitting, as shown in FIG. 20, thecross-sectional area of fluid delivery hole 121' of the base portion 12'continuing from the head portion 11' has the equal cross-sectional areato that of the fluid delivery hole 211' of the nipple 2'.

A machining process, in which a prescribed raw material is machined to ahose fitting, has been known as a process for manufacturing theconventional hose fitting.

PROBLEM WITH THE PRIOR ART

The conventional hose fitting is relatively heavy in weight. And sincethe cross-sectional area of the fluid delivery hole 121' of the baseportion 12' has the equal cross-sectional area to that of the fluiddelivery hole 211' of the nipple 2', the base portion 12' cannot be bentby a sharp angle without making the cross-sectional area of the fluiddelivery hole 121' smaller than that of the fluid delivery hole 211' ofthe nipple 2' when bending the base portion 12'.

The conventional process for manufacturing the hose fitting by machininghas complicated manufacturing processes, causes a large amount ofmaterial loss, and is expensive.

Furthermore, in the conventional hose fitting, the nipple 2' should befixed on the bottom surface of the sleeve 13' in a fluid-tight manner bybrazing or drive fitting the nipple 2' so as not to have the fluidpassing through the fluid delivery hole 211' of the nipple 2' leakedthrough an engaging portion between the sleeve 13' and the nipple 2',and avoid the oil intruding into the hose end surface.

SUMMARY OF THE INVENTION

Accordingly it is an object of this invention to solve theabove-mentioned problems. In other word, it is an object of thisinvention to provide a hose fitting having the following advantages anda process for manufacturing such hose fitting economically with lessmaterial loss.

1. A hose fitting requiring less workload to bend the base portion, andoffering easy work for the bending.

2. A hose fitting securing a necessary cross-sectional area as the fluiddelivery hole of the base portion even when the base portion is bentgreatly.

3. A hose fitting being lighter than the conventional hose fittings,having a uniform wall thickness, and requiring less raw material cost.

4. A hose fitting in which the nipple is fixed on the sleeve innercircumferential surface in a fluid-tight manner without brazing or drivefitting the nipple.

The hose fitting of this invention comprises a hose fitting bodycomposed of a head portion which is formed by pressing a testtube-shaped substance at the bottom to flatten the cylindrical surfaceat the bottom while leaving space inside thereof, and then by forming athrough hole in the center of the flattened cylindrical surface at thebottom, a base portion composed of the intermediate portion of the testtube-shaped substance continuing from the head portion, a sleevecomposed of the opening end of the test tube-shaped substance continuingfrom the base portion, and a nipple integrally fixed on the innercircumferential surface of the sleeve.

It is preferred that the cross-sectional area of the fluid delivery holeof the base portion is from 5 to 30 times as much as that of the fluiddelivery hole of the nipple. This is because to secure a necessarycross-sectional area as the fluid delivery hole of the base portion evenafter bending the base portion.

Further, it is preferred that the head portion composed of the flattenedcylindrical surface at the bottom has a flat shape in which in thevertical cross-sectional view the length is from 1 to 3 times as much asthe height. When the above-mentioned head length is smaller than theabove-mentioned head height, it is disadvantageous to secure the sealbetween the hose fitting and the mating member, but advantageous tosecure the fluid delivery amount. Contrarily, when the head length islarger than 3 times of the head height, it is advantageous to secure theseal between the hose fitting and the mating member, but disadvantageousto secure the fluid delivery amount.

The hose fitting of this invention is manufactured by a manufacturingprocess comprising the following steps:

a first step for manufacturing a test tube-shaped substance whoseopening end is to be a sleeve and whose bottom end is to be a headportion by a plastic deformation on a metallic raw material;

a second step for forming flat top and bottom surfaces by pressing thecylindrical surface of the test tube-shaped substance at the bottomwhile leaving space inside thereof;

a third step for forming a through hole into which a bolt is to beinserted by punching the flat top and bottom surfaces at the center;

a fourth step for fixing a nipple having a coaxial fluid delivery holewith the opening of the test tube-shaped substance on the innercircumferential surface of the opening of the test tube-shaped substanceto be the sleeve.

The metallic raw material used in the first step may be a plate-shapedsubstance, a square shaped substance with a large wall thickness, arectangular solid shaped substance, or a lump of substance.

The hose fitting of this invention can be manufactured by a smallworkload because it is manufactured out of the test tube-shapedsubstance.

Less workload is required for the bending of the base portion.Accordingly, it is easy to bend the base portion of the hose fitting ofthis invention.

It is easy to secure a necessary cross-sectional area for the fluiddelivery hole of the base portion when bending the base portion, becausethe cross-sectional area of the fluid delivery hole of the base portionis larger than that of the fluid delivery hole of the nipple in the hosefitting of this invention.

The hose fitting obtained by this invention is lighter than theconventional hose fitting, and has an approximately uniform wallthickness.

Since the manufacturing process of this invention is drawing, it is lessexpensive and easier than the conventional manufacturing process inwhich the hose fitting is formed by machining. And the manufacturingprocess of this invention offers less material loss than theconventional manufacturing process does. In addition, at least the wallthicknesses of the base portion and the sleeve can be made approximatelyuniform by the manufacturing process of this invention.

The fluid intrusion into the hose end surface can be prevented withoutfixing the nipple on the bottom surface of the sleeve by brazing ordrive fitting in the hose fitting of this invention.

Furthermore, since the nipple used in the hose fitting of this inventionis manufactured by drawing, it can be manufactured with less materialloss than by machining. Further the wall thickness of the nipple can bemanufactured to be approximately uniform.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a hose fitting concerning a firstpreferred embodiment.

FIG. 2 is a plan view of the hose fitting illustrated in FIG. 1.

FIG. 3 is a vertical cross-sectional view of the hose fittingillustrated in FIG. 1.

FIG. 4 is an explanatory cross-sectional view illustrating a greatlybent base portion of the hose fitting illustrated in FIG. 1.

FIG. 5 is a plan view of a hose fitting concerning a second preferredembodiment.

FIG. 6 is a vertical cross-sectional view of the hose fittingillustrated in FIG. 5.

FIG. 7 is an explanatory cross-sectional view illustrating a caulkedhose fitting illustrated in FIG. 5 into which a hose is inserted.

FIG. 8 is an explanatory cross-sectional view illustrating a greatlybent base portion of the hose fitting illustrated in FIG. 5.

FIG. 9 is a cross-sectional view of the part of a plate-shaped metallicraw material for manufacturing the hose fitting body of the first andsecond preferred embodiments.

FIG. 10 is an explanatory cross-sectional view of a test tube-shapedsubstance manufactured by drawing the plate-shaped metallic raw materialillustrated in FIG. 9.

FIG. 11 is a perspective view of top and bottom surfaces formed byflattening the cylindrical surface of the test tube-shaped substance atthe bottom illustrated in FIG. 10.

FIG. 12 is an explanatory view of a through hole formed by punching theflattened top and bottom surfaces at the center, which are formed byflattening the cylindrical surface of the test tube-shaped substance atthe bottom illustrated in FIG. 11.

FIG. 13 is a cross-sectional view of the part of a plate-shaped metallicraw material for manufacturing a nipple in the second preferredembodiment.

FIG. 14 is an explanatory cross-sectional view of a nipple body formedby drawing the plate-shaped metallic raw material illustrated in FIG.13.

FIG. 15 is an explanatory cross-sectional view of a start of an outercylinder portion and bottom portion forming by drawing thecircumferential portion of the nipple body illustrated in FIG. 14 in thedirection opposite to the drawing in FIG. 14, namely in the upperdirection of this figure.

FIG. 16 is an explanatory cross-sectional view of the outer cylinderportion surrounding the nipple body formed by further drawing thesubstance illustrated in FIG. 15.

FIG. 17 is an explanatory cross-sectional view of a nipple used in thesecond preferred embodiment in which the end of the outer cylinderportion is cut after making a fluid delivery hole opening on the nipplebody illustrated in FIG. 16.

FIG. 18 is a vertical cross-sectional view of a hose intermediatefitting body used in a third preferred embodiment in which the nipplesused in the second preferred embodiment are installed.

FIG. 19 is a vertical cross-sectional view of a hose fitting body usedin a fourth preferred embodiment in which the nipple used in the secondpreferred embodiment is installed.

FIG. 20 is an explanatory cross-sectional view of a conventional hosefitting.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be hereinafter explained with reference topreferred embodiments.

(First Preferred Embodiment)

A perspective view of a hose fitting of this preferred embodiment isillustrated in FIG. 1, a plan view of the same is illustrated in FIG. 2,and a vertical cross-sectional view of the same is illustrated in FIG.3.

This hose fitting comprises a hose fitting body 1 and a nipple 2. Thehose fitting body 1 comprises a head portion 11, a base portion 12continuing from the head portion 11, and a sleeve 13 continuing from thebase portion 12.

The head portion 11 is formed by pressing the cylindrical surface of atest tube-shaped substance at the bottom to flatten the cylindricalsurface thereof at the bottom while leaving space inside thereof, andthen by forming a through hole 11 in the center of the flattenedcylindrical surface at the bottom.

The base portion 12 is composed of the intermediate portion of the testtube-shaped substance continuing from the head portion 11. And thesleeve 13 is composed of the opening end of the test tube-shapedsubstance continuing from the base portion 12.

The cross-sectional area of the fluid delivery hole 121 of the baseportion 12 is from 5 to 20 times as much as that of the fluid deliveryhole 211 of the nipple 2.

And the head portion 11 composed of the flattened cylindrical surfacehas a length approximately 1.5 times as much as a height in the verticalcross-sectional view. In addition, a concave 112 is formed in the endsurface and side surfaces of the head portion 11.

The nipple 2 of this preferred embodiment is fixed integrally on theinner circumferential surface of the sleeve 13. And the nipple 2 iscomposed of a cylindrical nipple body 21, and a flange portion 22integrally formed on one end of the nipple body 21 to be fixed on theinner circumferential surface of the sleeve 13. The nipple 2 ismanufactured out of a plate-shaped metallic raw material by drawing.

The hose fitting of this preferred embodiment is manufactured asfollows:

(1) Manufacturing of the Hose Fitting Body 1

First, a plate-shaped metallic raw material 100 shown in FIG. 9 isprepared, and is deformed plastically by drawing to manufacture a testtube-shaped substance shown in FIG. 10. The bottom end 110 of the testtube-shaped substance becomes the head portion 11 of the hose fittingbody 1, and the intermediate portion 120 thereof becomes the baseportion 12 of the hose fitting body 1, and the opening end 130 thereofbecomes the sleeve 13 of the hose fitting body 1.

Then, as shown in FIG. 11, top and bottom surfaces 113 are formed bypressing the cylindrical surface of the bottom end 110 of the testtube-shaped substance. The cylindrical surface is flattened whileleaving space inside the test tube-shaped substance.

And then, as shown in FIG. 12, after inserting a mandrel 50 into thetest tube-shaped substance with thus formed top and bottom surfaces 113,the flattened top and bottom surfaces 113 are punched at the centerthereof by a tool 60 to form a through hole 111 into which a bolt is tobe inserted.

In addition, as shown in FIGS. 1 through 3, the hose fitting of thisinvention has the concave 112 in the end surface and side surfaces ofthe head portion 11. The concave 112 is formed by placing prescribeddies on the end surface and side surfaces of the head portion 11 andpressing the dies in the inward direction to the hose fitting body 1;i.e. in the right, upper and lower directions in FIG. 2, and in theright direction in FIG. 3.

Thus, the hose fitting body 1 with the through hole 111 is manufactured.

(2) Installing Nipple 2 in the Hose Fitting Body 1

After inserting the nipple 2 inside the sleeve 13, the nipple 2 is fixedon the inner circumferential surface of the sleeve 13 by caulking thesleeve at one end thereof inwardly in the radical direction.

The wall thickness of the hose fitting body 1 is approximately uniform,and is manufactured with less material loss than it is manufactured bymachining, since the hose fitting body 1 is manufactured out of onepiece of the plate-shaped metallic raw material 100 by drawing.

As can be readily understood from FIG. 3, it is easy to secure anecessary cross-sectional area for the fluid delivery hole 121 of thebase portion 12 even when bending the base portion 12, since thecross-sectional area of the fluid delivery hole 121 of the base portion12 is from 5 to 20 times as much as that of the fluid delivery hole 211of the nipple 2.

Further, the head portion 11 contacts with the mating member in asurface-on-surface manner, since the top and bottom surfaces 113 of thehead portion 11 is flattened as illustrated in FIGS. 1 through 4, andFIG. 11. Accordingly, such an arrangement is effective to secure theseal between the hose fitting and the mating member.

Furthermore, the hose fitting of this preferred embodiment can fullybear a fastening of a considerable force when assembled with the matingmember, since the hose fitting of this preferred embodiment has the headportion 11 with the concave 112 formed in the end surface and the sidesurfaces thereof, and the concave 112 provides a reinforcement effect.

(Second Preferred Embodiment)

A plan view of a hose fitting of this preferred embodiment isillustrated in FIG. 5, a vertical cross-sectional view thereof isillustrated in FIG. 6, an explanatory cross-sectional view of the hosefitting with a hose inserted and with the sleeve caulked is illustratedin FIG. 7, and an explanatory cross-sectional view of the hose fittingwith a bent base portion is illustrated in FIG. 8.

A nipple 2a, shown in FIG. 17, is used in the hose fitting of thispreferred embodiment. The nipple 2a is manufactured out of aplate-shaped metallic raw material by drawing.

The hose fitting of this invention comprises a hose fitting body 1a andthe nipple 2a. A hose fitting body, which is identical to the one usedin the first preferred embodiment but no concave 112 is formed in theend surface and the side surfaces of a head portion 11a, is used as thehose fitting body 1a.

The nipple 2a of the hose fitting of this preferred embodiment comprisesa cylindrical outer cylinder portion 23a to be contacted and fixed onthe inner circumferential surface of a sleeve 13a, a disk shaped bottomportion 24a continuing from one end of the outer cylinder portion 23aand extending radially, and a cylindrical nipple body 21a continuingfrom the bottom portion 24a and extending coaxially with the outercylinder portion inside the outer cylinder portion.

The nipple 2a is inserted into the sleeve 13a of the hose fitting body1a, and fixed tightly on the inner circumferential surface of the sleeve13a.

And the cross-sectional area of a fluid delivery hole 121a of the baseportion 12a is approximately from 5 to 20 times as much as that of afluid delivery hole 211a of the nipple body 21a of the nipple 2a.

The hose fitting of this preferred embodiment is manufactured asfollows:

(1) Manufacturing of the Hose Fitting Body 1a

The hose fitting body 1a of this preferred embodiment is manufactured bythe identical manufacturing process for the hose fitting body 1 of thefirst preferred embodiment.

(2) Manufacturing of the Nipple 2a

First, a plate-shaped metallic raw material 200 shown in FIG. 13 isprepared, and is deformed plastically by drawing to form a testtube-shaped substance to be the nipple body 21a shown in FIG. 14. Thedrawing is identical process to the manufacturing process of the hosefitting of the first preferred embodiment; i.e. "(1) Manufacturing ofthe Hose Fitting Body 1".

Then, as shown in FIG. 15, the forming of the outer cylinder portion 23asurrounding the nipple body 21a coaxially, and the disk shaped bottomportion 24a continuing from one end of the outer cylinder portion 23aand extending radially is started by plastically deforming thecircumferential portion of the raw material 200 continuing from theopening end of the test tube-shaped substance to be the nipple body 21ain the opposite direction; i.e. by drawing in the upper direction inFIG. 15. The drawing in the upper direction in FIG. 15 is furtherperformed to form the outer cylinder portion 23a surrounding theperiphery of the nipple body 21a integrally as shown in FIG. 16.

And then, as shown in FIG. 17, a fluid delivery hole opening 212a isformed by making an opening at the center of the end of the cylindricalnipple body 21a. And the end of the cylindrical outer cylinder portion23a is cut to a predetermined shape.

Thus, the nipple 2a is manufactured. It comprises the following asmentioned earlier: the nipple body 21a having the fluid delivery holeopening 212a, the cylindrical outer cylinder portion 23a, and the diskshaped bottom portion 24a continuing from one end of the outer cylinderportion 23a and extending radially.

(3) Installing the Nipple 2a in the Hose Fitting Body 1a

As shown in FIG. 6, the nipple 2a is installed in the sleeve 13a of thehose fitting body 1a having a through hole 111a, and is fixed on theinner circumferential surface of the sleeve 13a of the hose fitting body1a so that the fluid delivery hole opening 211a of the nipple 2a iscoaxial with the opening of the sleeve 13a.

As shown in FIG. 7, the hose fitting of this preferred embodiment isused as a hose assembly after inserting the hose 9 between the nipplebody 21a and the outer cylinder portion 23a, and caulking the sleeve13a.

The hose fitting of this preferred embodiment has the followingadvantages in addition to the advantages of the first preferredembodiment.

The nipple 2a is manufactured out of one piece of plate-shaped metallicraw material 200 by drawing. Hence, the wall thickness of the nipple 2acan be made approximately uniform. And the nipple 2a can be manufacturedwith less material loss than it is manufactured by machining.

Further, the oil intrusion through the fluid delivery hole 121a of thebase portion 12a into the hose end surface can be prevented, since thenipple body 21a and the outer cylinder portion 23a are formedintegrally, and the hose 9 is inserted between them.

In addition, the fluid delivery cannot be disturbed even when the baseportion 12a of the hose fitting body 1a is bent by about bent angles of30 to 120 deg as shown in FIG. 8, since the cross-sectional area of thefluid delivery hole 121a of the base portion 12a is approximately from 5to 20 times as much as that of the fluid delivery hole 211a of thenipple 2a.

Moreover, as shown in FIG. 7, the hose 9 is inserted between the nipplebody 21a and the outer cylinder portion 23a, and then the sleeve 13a iscaulked. Consequently, the nipple 2a is fixed in the sleeve 13a firmly,and therefore the hose 9 disengagement from the nipple 2a can beprevented, since the sleeve 13a is in close contact with the outercylinder portion 23a of the nipple 2a.

The hose fitting having an approximately uniform wall thickness can bemanufactured out of a plate-shaped metallic raw material by a simple andconvenient process; i.e. a plastic deformation. Further, theabove-mentioned manufacturing process offers less material loss than theconventional manufacturing process by machining.

(Third Preferred Embodiment)

In this preferred embodiment, the nipple 2a manufactured and used in thesecond preferred embodiment is applied to a hose intermediate fittingbody 1b for connecting two hoses. The vertical cross-sectional view ofthe hose intermediate fitting body 1b is shown in FIG. 18.

The hose intermediate fitting body 1b is a cylindrical metalliccomponent having a base portion 14, two deep holes at both ends of thebase portion 14 forming a first sleeve 15 and a second sleeve 16 inwhich the nipples 2a are installed. The two deep holes are connected byan internal through hole 17 having less diameter than the diameter ofthe deep holes which works as a fluid delivery hole. In addition, aprojection for engaging with a mating member is formed on and around theouter circumferential surface of the base portion 14 of the hoseintermediate fitting body 1b.

The first sleeve 15 and the second sleeve 16 of the hose intermediatefitting body 1b are caulked after installing the nipples 2a into thefirst sleeve 15 and the second sleeve 16, and inserting the hoses 9 intothe nipples 2a. In this case, too, the fluid intrusion through theinternal through hole 17 into the end surfaces of the hoses 9 can beprevented without brazing or drive fitting the nipples 2a to the hoseintermediate fitting body 1b.

(Fourth Preferred Embodiment)

In this preferred embodiment, the nipple 2a manufactured and used in thesecond preferred embodiment is applied to a hose fitting body 1c whosevertical cross-sectional view is shown in FIG. 19.

The hose fitting body 1c has a base portion 12c having a fluid deliveryhole 121c, and a sleeve 13c formed continually from one end of the baseportion 12c. The nipple 2a is installed in the sleeve 13c. Afterinserting a hose into the nipple 2a, the sleeve 13c is caulked so as topress the outer cylinder portion of the nipple 2a and the outercircumferential surface of the hose. In this case, too, the fluidintrusion through the fluid delivery hole 121c into the hose end surfacecan be prevented without brazing or drive fitting the nipple 2a to thehose fitting body 1c.

Obviously, this invention is not limited to the above teachingsexplained as the preferred embodiments. Depending on objects or usages,numerous modifications and variations of this invention can be givenpreferred embodiments in right of this invention.

Hence, the hose fitting of this invention is not limited to the casewhere the cross-sectional area of the fluid delivery hole of the baseportion is approximately from 5 to 20 times as much as that of the fluiddelivery hole of the nipple. The cross-sectional area of the fluiddelivery hole of the base portion can be freely made greater than thatof the fluid delivery hole of the nipple. Such modification on the ratioof the cross-sectional areas can be freely set by changing the pressingdegree of the cylindrical surface at the bottom of the test tube-shapedsubstance manufactured in the first step of the above-mentioned hosefitting manufacturing process.

Further, the nipple may not necessarily be manufactured by drawing likethe nipple 2a of the second preferred embodiment. It may be manufacturedby machining. In addition, the nipple may be manufactured not only outof the plate-shaped metallic raw material but also out of a rectangularsolid shaped substance having a large wall thickness by cold forming.

Furthermore, when manufacturing a hose assembly comprising a hose andhose fittings, the hose may be first inserted into the nipple, and thenthe nipple with the hose inserted may be installed in the sleeve of thehose fitting body, contrary to the procedure of the above-mentionedpreferred embodiments; i.e. the nipple is first inserted into the sleeveof the hose fitting body, and then the hose is inserted in the nipple.

What is claimed is:
 1. A process for manufacturing a hose fitting,comprising the following steps of:a first step of manufacturing acylindrical test tube-shaped element whose opening end is to be a sleeveand whose bottom closed end is to be a head portion by a plasticdeformation on a flat plate metallic raw material; a second step offorming flat top and bottom surfaces by pressing the cylindrical surfaceof said test tube-shaped element at the bottom closed end while leavingspace inside thereof; a third step of forming a through hole into whicha bolt is to be inserted by punching said flat top and bottom surfacesat the center; a fourth step of fixing a nipple having a coaxial fluiddelivery hole with the opening end of said test tube-shaped element onthe inner circumferential surface of the opening end of said testtube-shaped element to be said sleeve with an outer portion of saidnipple spaced from an inner portion of said opening end.
 2. A processfor manufacturing a hose fitting according to claim 1,wherein said hosefitting has a nipple produced by a process comprising the followingsteps of: a first step of manufacturing an element having a cylindricaltest tube-shaped portion in center to be a nipple body by a plasticdeformation on a flat plate metallic raw material, a second step ofmanufacturing a cylindrical element having an outer cylinder portionsurrounding said nipple body coaxially by a plastic deformation on thecircumferential portion of said element having said cylindrical testtube-shaped portion in center manufactured in the first step of thenipple producing process in the direction opposite to the plasticdeformation of said first step of the nipple producing process; and athird step of forming a fluid delivery hole opening by making an openingat the top center of said cylindrical element manufactured in saidsecond step of the nipple producing process.